Johann Friedrich Blumenbach (1752–1840) divided the human species into five races in 1779, later founded on crania research (description of human skulls), and called them (1793/1795):
the Caucasian race
the Mongoloid race
the Malay race
the Negroid race
the American race
Caucasian race (also Caucasoid[1] or Europid[2]) has historically been used to describe the physical or biological type of some or all of the populations of Europe, North Africa, the Horn of Africa, Western Asia, Central Asia, and South Asia.[3] The term was used in biological anthropology for many people from these regions, without regard necessarily to skin tone.[4] First introduced in early racial science and anthropometry, the taxon has historically been used to denote one of the proposed major races of humankind.[5] Although its validity and utility is disputed by many anthropologists, Caucasoid as a biological classification remains in use,[6] particularly within the field of forensic anthropology.
The postulated subraces vary depending on the author, including but not limited to Mediterranean, Atlantid, Nordic, Alpine, Dinaric, Turanid, Armenoid, Iranid, Arabid, and Hamitic.
In 1920, H. G. Wells referred to the Mediterranean race as the Iberian race. He regarded it as a fourth sub-race of the Caucasoid race, along with the Aryan, Semitic, and Hamitic sub-races. He stated that the main ethnic group that most purely represented the racial stock of the Iberian race was the Basques, and that the Basques were the descendants of the Cro-Magnons.[28]
A Possible Explanation Why there hasn’t been much effort to refine the definitions of races since the 1930’s:
Several social and political developments that occurred at the end of the 19th century and into the 20th century led to the transformation in the discourse of race. Three movements that historians have considered are: the coming of mass democracy, the age of imperialist expansion, and the impact of Nazism.[19] More than any other, the violence of Nazi rule, the Holocaust, and World War II transformed the whole discussion of race. Nazism made an argument for racial superiority based on a biological basis. This led to the idea that people could be divided into discrete groups and based on the divisions, there would be severe, tortuous, and often fatal consequence. The exposition of racial theory beginning in the Third Reich, up to the Final Solution, created a popular moral revolution against racism.[19] In 1950, and as a response to the genocide of Nazism, UNESCO was formed and released a statement saying that there was no biological determinant or basis for race.
Consequently, studies of human variation focused more on actual patterns of variation and evolutionary patterns among populations and less about classification. Some scientists point to three discoveries. Firstly, African populations exhibit greater genetic diversity and less linkage disequilibrium because of their long history. Secondly, genetic similarity is directly correlated with geographic proximity. Lastly, some loci reflect selection in response to environmental gradients. Therefore, some argue, human racial groups do not appear to be distinct ethnic groups.[20]
~from a variety of Wkipedia articles